A growing footprint

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Wide singles have been slow to catch on among owner-operators, but their fuel-saving advantages open the door for more sales.

Wide single tires initially were used by fleets specializing in weight-sensitive loads, where a small reduction in truck weight could increase the payload. These tires, in sizes such as 445/65R22.5 and commonly known as “super singles,” had a higher rolling radius than most over-the-road duals. So they required expensive retrofitting, including adjustments in gear ratios. radius than most over-the-road duals. So they required expensive retrofitting, including adjustments in gear ratios.

In 2000, Michelin replicated the rolling radius of various popular dual-tire sizes (low-profile 22.5s, deep-lug 11R22.5s and low-pro 24.5s) with its X One wide-base singles. Since then, converting to singles has required only a “bolt-on solution,” as X One Product Manager Michael Burroughes calls it: a 14-inch-wide wheel takes the place of a dual pair.

Bridgestone followed shortly with its Greatec, the other wide single available in the United States.

A small number of owner-operators outside the weight-sensitive niche have recognized the benefits: reduced weight, improved fuel economy and simpler maintenance. Different messages from competing manufacturers, fear of a blowout and simple resistance to trying something new have kept the majority away. But high fuel prices alone might accelerate the slow but steady trend of conversion to wide singles, which by some estimates can add thousands of dollars per year to the bottom line from fuel savings and increased payloads.

Michelin and Bridgestone won’t release numbers, but they say sales are steadily increasing. Michelin has three times expanded its X One plant in Spartanburg, S.C., and it plans to expand its Nova Scotia plant in 2007 and dedicate production to X Ones. Bridgestone continues to invest in singles, developing their Aircept inner liners in conjunction with an electronic stability program to prevent total tire failure in the event of a rapid decrease in pressure.

Owner-operator Andy Soucy of Lebanon, Tenn., put X Ones on his Western Star tandem-axle tractor in February. So far, he’s happiest with an unexpected benefit: “The harshness of the bumps – you still feel bumps, of course – has been mostly eliminated.” As Burroughes says, wide tires have the ability to absorb more energy than traditional tires, and a slight increase in the overall track width means the truck is more stable.

But Soucy’s primary concern was weight. “I pull a drop deck,” Soucy says, and though most of his loads are under 25,000 pounds, “I’ve got a generator on the truck, and over the years, adding equipment, I’ve gotten up to 33,700 pounds.” The occasional 46,000-pound load would leave him dangerously close to the weight limit. The wide singles allowed him to gain back, according to Michelin’s product formulas, about 400 pounds.

Doug Gorenflo of Baltimore, who’s leased to Quality Carriers, typically pulls chemical tankers and was concerned about how singles would handle in adverse weather. He did have a scare when he almost lost control after hitting the brakes in the rain once when his tanker was empty. “But when I’m loaded, I have no worries at all,” he says.

“The biggest selling point in the industry has been to the fleets where weight is an issue,” says Kevin Rutherford of Orlando, Fla., an owner-operator business consultant who also runs a small fleet. But outfitting your drive axles with singles on aluminum rims saves you a mere 400 pounds in tire and wheel weight if you’re already running on aluminum, Rutherford says. Some of the higher estimates of weight savings are based on conversion from steel wheels and duals on both drive and trailer axles to aluminum wheels and singles.

“The biggest advantage behind a super single is lower rolling resistance,” Rutherford says. “And the easier a tire rolls, the less fuel it takes just to get it down the road.” He recently outfitted one of his trucks, a single-axle tractor leased to FedEx on a dedicated run, with singles on the drive axle to test fuel efficiency. He installed a new set of duals beforehand so that he could make accurate comparisons of fuel efficiency. Since converting he’s seen an increase of two-tenths of a mile per gallon, or 4 percent.

Converting from 18 wheels to 10 “will achieve a minimum of 4 percent fuel savings,” Burroughes says. “Changing from a deep-lug high-mileage tire to a deep-tread X One, you’ll get a minimum 4 percent change as well.”

The cost and availability of wide singles, especially in emergencies, has been another concern. The X One is available at every authorized Michelin dealer in the country, in addition to many major truck stops. The Bridgestone Greatec, too, is available through authorized dealers in the 445/50R22.5 size to replace low-profile 22.5 duals. Bridgestone continues to view the wide single, however, as a niche product for weight-sensitive haulers, says spokesman Don Darden.

Rutherford and others have seen wide singles advertised for as much as $1,000 apiece. For example, the Petro in New Paris, Ohio, has singles mounted on an aluminum rim and ready to go for around $1,500, including the rim.

But Michelin and Bridgestone have offered deals that include trade-ins of duals and rims, reducing the cost of the tires to the neighborhood of $650, just slightly higher than a pair of duals at roughly $300 apiece. Even if you can’t use a fleet account or similar discount program, Rutherford says, “You can do much better than $1,000 apiece if you just keep looking.”

Prices might well trend downward as availability increases. “As more manufacturers enter the market,” says Darden, “that also may drive more market penetration for the technology.” These tires also are retreadable; Michelin Retread Technologies franchises do them, as do Bandag and other independents.

While Soucy and Gorenflo have so far seen wear rates comparable to their old duals, Darden notes this might not always be the case: “Some fleets and users have discovered that drive tire mileage of wide-base tires is not usually equal to that of duals because the wide-base has a slightly smaller footprint but must carry the same or greater load, thus working harder and wearing faster.”

Overall savings estimates from wide tires vary widely. It appears you can save $1,000 or more in fuel economy if you’re already running fuel-efficient duals. Though, as Rutherford points out, many owner-operators favor high-mileage tires, and savings on a conversion from singles in that case might be more than $2,000. If you can combine that with increased payload, conversion to a 10-wheeler could pay for itself sooner than you think.

BRIDGESTONE: (800) 815-9793, website
MICHELIN: (877) 966-3911, website

CONTINENTAL TIRE NORTH AMERICA. The company had announced a wide single release for late 2006 but is now looking at late 2007, says Curtis Decker, manager of field engineering. “We want a product that’s competitive,” Decker says.

GOODYEAR. “We view super single tires as a niche product,” says spokesman Dave Wilkins. “Some questions on the tires haven’t been answered – durability, retreadability, cost of conversion, serviceability – but we continue to evaluate the concept.”

YOKOHAMA. A wide single is in development, and the company has “plans to begin evaluations in the U.S. sometime in 2007,” says Sales Director John Cooney.

Versailles, Ohio, owner-operator John Roquemore, whose Volvo with a 12.5-foot custom sleeper pulls an enclosed car hauler, hasn’t felt good about his singles ever since he heard a horror story. A realignment guy in Twin Falls, Idaho, told him the average service call on a wide-single blowout, due to damage beyond the tire, was in the $2,500 range.

“When you blow one of these, you’ve got to change not only the tire, but the wheel, the fender covers,” Roquemore says. He’s waiting for an owner-operator to come along who’s willing to swap duals for his singles. “I’d switch back in a heartbeat.”

Roquemore recently got a nail near the sidewall in one of his singles – a hole that couldn’t be patched – and the replacement tire was around $800 after his fleet’s national account savings. If he’d been running duals, that replacement likely would have cost less than half that.

True, you can’t “limp” into the next stop when running a wide single. Nor should you, for safety reasons, and manufacturers don’t recommend wides for single-drive-axle tractors unless they’re outfitted with electronic stability programs that take control in the event of a catastrophic loss of air pressure (in the case of Bridgestone, that company’s Aircept system). Even with two drive axles, limping in is not only dangerous but illegal, says small-fleet owner Kevin Rutherford.

However, Rutherford and owner-operator Andy Soucy both downplay the risk of high tire replacement costs, asking: When was the last time you blew a drive tire?

“I’ve never blown a virgin drive tire on this truck,” says Soucy of his Western Star. “Of the two trucks I’ve had over the past 10 years, I’ve only blown once. And that was a valve-stem failure which I didn’t realize.”

Doug Gorenflo says a fellow tanker owner-operator had no trouble getting a wide tire when, on a tight refinery delivery, he ran afoul of a piece of metal. “They were out there in about 45 minutes,” Gorenflo says. “I think with the service call and buying the tire it cost him a grand.”

Chances of a blowout are further minimized by the ease of checking the pressure of a wide single versus a dual pair. Fleets running the X One have reported a much lower incidence of flats because the majority of flats occur on inside duals, where it’s difficult to check pressure, Burroughes says. Gorenflo and Soucy have been impressed by how quickly they’re able to recognize a pressure imbalance in wides because of the vibration it sends through their vehicles.

The U.S. government has found ways to bestow its blessings on wide singles.

On Jan. 1, 2005, the federal excise taxes on wide singles decreased, and those on traditional tires went up. For example, one Bridgestone Greatec drive-axle single carries a $31.66 FET, as compared to $50.46 on a pair of that manufacturer’s M726 EL standard drive-axle duals, as is noted in a Bridgestone sales brochure.

The wide single is the heavy-truck tire of choice for the U.S. Environmental Protection Agency’s SmartWay Transport Partnership, a collaboration with the freight industry designed to increase energy efficiency. The program includes incentives and loans to encourage conversion, and its 2005 study calculated an increase of 8 percent to 12 percent in fuel efficiency through conversion to wide singles on the drive and trailer axles.

“The incentive for carrier companies to join the partnership is embedded in the carrier-shipper relationship,” says SmartWay Manager Mitchell Greenberg. “Shippers who join SmartWay need to use carriers that are SmartWay partners. Furthermore, shippers get more credit for using high-performing carriers, so there is incentive for carriers to continually improve their efficiency.”

Bridgestone’s Don Darden says the EPA also encourages use of fuel-efficient duals, which most tire manufacturers have developed. “There are duals designed for low rolling resistance that offer fuel economy equal to or even better than the 50-series tires,” he says, “without the need to invest in different tire sizes or new, unique wheels.”

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